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DOI 10.5286/raltr.2009007
Persistent URL http://purl.org/net/epubs/work/50208
Record Status Checked
Record Id 50208
Title A note on a simple constrained ordering for saddle-point systems
Contributors
Abstract A well-known problem with sparse direct solvers is that, if numerical pivoting is required, the number of entries in the computed factors can be significantly greater than the number predicted on the basis of the sparsity pattern alone. In this note, we review a simple constrained ordering recently proposed by Bridson [1] for sadle-point systems. Bridson's approach allows the factorization to be computed without numerical pivoting but numerical experiments show that the computed factors are generally significantly denser that those obtained by prescaling the matrix and then using an unconstrianed ordering combined with threashold partial pivoting
Organisation CSE , CSE-NAG , STFC
Keywords large sparse symmetric linear systems , pivoting , scaling , direct solvers
Funding Information
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Language English (EN)
Type Details URI(s) Local file(s) Year
Report RAL Technical Reports RAL-TR-2009-007. STFC, 2009. sRAL2009007.pdf 2009